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Journal Watch by Sean Henahan Vision science highlights from the world’s leading journals of medicine and science

LASIK in patients with significant finding for functional outcome was proliferative retinopathy. Those with high to make early in development and a worsened refractive outcome in the HbA1C levels and high blood pressure at the individually migrate to the right place to do systemic contraindications collagen vascular diseases group compared beginning of the study were more likely to so.The study overturns the textbook model It may be time to reconsider the current with controls. No other statistical differences develop progressive diabetic retinopathy, of the process and suggests that other organs absolute exclusion of certain systemic were detected in the other systemic disease proliferative retinopathy and macular might also be formed by the movement of contraindications to LASIK, say Spanish groups. oedema. Development of proliferative single cells rather than sheets of entire researchers.They conducted an observational retinopathy also was associated with older tissues. Jochen Wittbrodt and colleagues retrospective case-control study to R Cobo-Soriano et al., Ophthalmology,‘LASIK age, kidney disease and more severe made the discovery using advanced determine the anatomic and functional outcomes in patients with underlying systemic retinopathy at the beginning of the study. microscope techniques to track individual outcomes of photorefractive surgery in contraindications: a preliminary study’, Macular oedema was associated with older cells in the transparent embryos of a small patients with underlying systemic diseases 2006;113(7):1124.e1. age, lower socioeconomic status, more severe fish called Medaka. The research builds on traditionally listed as relative or absolute retinopathy and higher total cholesterol earlier work showing that a protein called contraindications. The study included 275 levels. Rx3 is required for formation. Only cells eyes of 141 consecutive patients who Diabetic retinopathy that will become the eye begin producing this MS Roy,Arch Ophthalmol.,‘Six-Year Progression underwent a LASIK procedure with any of associated with poor blood molecule early on in development. The of Retinopathy and Associated Risk Factors in the following underlying conditions: researchers labelled these cells with a glucose control African American Patients With Type 1 Diabetes autoimmune connective-tissue disorders (62 fluorescent marker and tracked them using A six-year study of African Americans with Mellitus,’ 2006; 124:1297-1306. patients); psoriasis (91 patients); intestinal advanced software. The process involved Type 1 diabetes showed a strong link between inflammatory diseases (67 patients); diabetes following thousands of cells and assembling poor glucose control and progression of (44 patients); and history of keloid formation tens of thousands of images into 3D movies. (18 patients). Twenty-nine patients (56 eyes) diabetic retinopathy. Hypertension was also a A new look at ocular were receiving systemic immunosuppressive significant factor for retinopathy progression. embryology M. Rembold et al., Science,‘Individual cell therapy.The control group included 358 eyes The study followed 483 patients with Type 1 migration as the driving force for optic vesicle New European research calls into question of 181 otherwise normal healthy patients diabetes. Patients underwent regular retinal evagination’, 25 August 2006 25, 313: 1130- some of the basic tenets of ocular who underwent LASIK. Mild anatomic photography and clinical evaluations. 1134. development. Researchers at the European complications were observed in both the Participants who had diabetes for the longest Molecular Biology Laboratory (EMBL) in case and control groups, with no statistical period of time were most likely to develop Heidelberg report that cells are programmed differences between groups. The only diabetic retinopathy and to progress to

complications than microkeratomes. However,a small subset of patients develop significant JCRS Highlights corneal haze after IntraLase that may be associated with transient light sensitivity. WM Petroll and colleagues sought to understand the underlying cause of this haze by using by Associate Editor Thomas Kohnen confocal microscopy to evaluate 29 eyes of 20 that had undergone LASIK with IntraLase or intracorneal lens insertion (Permavision, Revision Optics) facilitated by IntraLase. The study indicated that both procedures could induce keratocyte activation, which may A closer look at pseudoaccommodation underlie, in part, clinical observations of haze and light sensitivity in some patients. They What are the ways to achieve pseudoaccommodative multifocal note that increased laser energy and larger step size in the raster pattern for flap creation vision? JCRS co-editor Douglas Koch MD addresses this may be associated with increased activation.They observed that intracorneal lens implants question in an editorial. He notes that all explanations of appear to induce chronic thinning of the overlying central corneal epithelium.They call for pseudoaccommodation involve a trade-off depth of focus is achieved at the expense of prospective evaluation of such eyes to determine whether epithelial thinning progresses sharpness of vision. His article includes a discussion of myopic astigmatism, coma and or stabilises over time. higher-order aberrations, bifocal and multifocal optics, and other potential factors. He WM Petroll et al, JCRS, ‘Confocal assessment of the corneal response to intracorneal lens directs the reader to a study by MA Nanavatyet al. that looked at factors contributing to insertion and laser in situ with flap creation using IntraLase’, July 2006, Vol. 32, pseudoaccommodation following and monofocal intraocular lens Issue 7, 1119-1128. implantation. The researchers conducted a case-controlled study comparing 30 patients with postoperative pseudoaccommodation and 30 patients without. They analysed factors Hydrodissection and PCO contributing to uncorrected visual acuity of at least 6/12 for distance and at least J4 for Does multiquadrant cortical cleaving hydrodissection reduce the development of posterior near after IOL implantation. Comprehensive clinical analysis showed a mean spherical capsule opacification after ? Indian researchers assessed this issue in a equivalent of -0.45 ± 0.63 D in eyes with pseudoaccommodation compared with -0.35 ± prospective randomised triple-blind clinical trial involving 86 eyes of 86 patients having 0.83 D in controls. Multivariate logistic regression highlighted corneal against-the-rule as a phacoemulsification.Although no difference was noted in the incidence of PCO, in eyes that significant factor in good uncorrected distance and near vision after monofocal IOL had PCO, the percentage of the area of the central posterior capsule involved by PCO was implantation. significantly lower in eyes that had multiquadrant cortical cleaving hydrodissection than in D Koch, JCRS,‘Revisiting the conoid of sturm’, July 2006,Vol. 32, Issue 7, 1071-1072. those that did not. MA Nanavaty et al., JCRS, ‘Analysis of patients with good uncorrected distance and near vision AR Vasavada, JCRS, ‘Effect of cortical cleaving hydrodissection on posterior capsule_opacification after monofocal intraocular lens implantation’, July 2006,Vol. 32, Issue 7, 1091-1097. in age-related nuclear cataract’, July 2006,Vol. 32, Issue 7 1196-1200.

Corneal response to IntraLase Femtosecond laser ablation (IntraLase) for LASIK flap creation is a new technique for keratorefractive surgery that appears to provide more consistent flap thickness with fewer

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